I used 1/4" glass dividers in my 55 sump. With a smaller tank, you may get away with 3/16", but I certainly wouldn't go down to 1/8". The 1/4" is pretty stout, but not too heavy or bulky to work with..... I'd recommend it. My local glass shop cut me two 12" x 15" panes, polished the edges, and rounded the bottom corners on one of the panes for $22.

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Wanna calculate the cost of that new reef tank?? Take your worst nightmare, double it, and you're halfway there.

What are the specs on your skimmer? 10" is about average. you can always put the skimmer on a platform to make the partitions higher if you want a deeper refugium, but don't forget to leave some room for the DT to drain into when the return pump is off.

In my 40B I'm going to run 12" of water. That should leave me plenty for my 210 DT to drain (IF my calculations are correct lol) What size is your tank so we have an idea of how much drain you would have?

do any of you know is that recommendation a minimum water height can the water go up that high on the skimmer or would I have to raise it 5" to have have a 10"water height in the sump. sorry if these are dumb questions. Just trying to understand it all.

do any of you know is that recommendation a minimum water height can the water go up that high on the skimmer or would I have to raise it 5" to have have a 10"water height in the sump. sorry if these are dumb questions. Just trying to understand it all.

You will have to raise it to the manufacturers water level recommendations